Folding Baby Stroller System and Method

ABSTRACT

A baby stroller for transporting an infant at speeds faster than normal walking is disclosed. This baby stroller can be folded to make it easier to stow and transport. The folding mechanism, a unique feature of the design is directed toward compactness, ease of use, reliability, and reduction in manufacturing costs.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. Ser. No. 12/041,137 filedMar. 3, 2010, which is a continuation of U.S. Ser. No. 11/254,922 filedOct. 20, 2005, which is a continuation of U.S. Ser. No. 10/430,688 filedMay 5, 2003, now U.S. Pat. No. 6,991,248.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to baby strollers, and more particularly,to all-terrain baby strollers that can be folded.

2. Description of the Related Art

Traditionally, baby strollers have been used to push an infant slowly ona relatively hard, smooth floor or sidewalk. As a result, the strollerswere made small and light. These strollers work well enough at slowspeed, but are extremely unwieldy and even dangerous on rough surfacesor at higher speeds.

All-terrain baby strollers have been designed to overcome theseProblems. These strollers typically employ much larger wheels, oftenlarge bicycle tires. The stroller frame members are constructed of metaltubular stock and durable plastic frame connectors or other durablematerial to connect the frame members together to handle the heavy dutyuse they may receive. The frame connectors are used also to rotate orpivot one frame member relative to another, and are used to removablyconnect other frame members together.

Some advanced designs of all-terrain strollers have allowed for acertain degree of folding of the all-terrain baby strollers into lessthan a desirable amount of compactness. In addition, conventionalfolding mechanisms include complications that increase cost and reducereliability and ease of use.

BRIEF SUMMARY OF THE INVENTION

The present invention resides in a folding baby stroller system andmethod. Embodiments include a front wheel and left and right sidelaterally spaced-apart front wheel supports. Each of the left and right&de front wheel supports has a forward end portion and a rearward endportion. The front wheel is mounted to the forward end portion of atleast one of the front wheel supports, the left and right side frontwheel supports being rotatable as a unit. Further included are left andright rear wheels, and left and right side laterally spaced-apart rearwheel supports. Each of the left and right side rear wheel supports hasa lower end portion and an upper end portion, the lower end portionsbeing coupled to at least one of the left and right rear wheels. Furtherincluded are left and right side laterally spaced-apart handle members.Each of the left and right side handle members has a forward end portionand a rearward end portion with a handle portion, the left and rightside handle members being rotatable as a unit. Further included are leftand right side laterally spaced-apart folding assemblies. Each of theleft and right side folding assemblies has a first rotatable member andsecond rotatable member rotatably coupled to a pivot member supported bythe upper end portion of a corresponding one of the left and right siderear wheel supports for rotation about a common axis of rotation andindependently rotatable relative to each other. The rearward end portionof a corresponding one of the left and right side front wheel supportsis fixedly attached to the first rotatable member, and the forward endportion of a corresponding one of the left and right side handle membersis fixedly attached to the second rotatable member.

Other features and advantages of the invention will become apparent fromthe following detailed description, taken in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is an isometric view of an exemplary implementation of a babystroller embodying the present invention shown in a fully unfolded stateready for usage.

FIG. 2 is an isometric view of the stroller frame of FIG. 1 without aseat and a leg guard.

FIG. 3 is a front elevational view of the stroller frame of FIG. 2.

FIG. 4 is a side elevational view of the stroller frame of FIG. 2.

FIG. 5 is a front elevational view of the stroller frame of FIG. 2 shownin a partially folded state with left and right front supports beingrotated about their respective side folding assemblies toward respectiveside rear wheel supports.

FIG. 6 is a side elevational view of the stroller frame of FIG. 2 shownin the partially folded state of FIG. 5.

FIG. 7 is a side elevational view of the stroller frame of FIG. 2 shownin a fully folded state with both left and right front supports and leftand right side handle supports being rotated about their respective sidefolding assemblies toward respective side rear wheel supports.

FIG. 8 is an exploded isometric view of one of left and right sidefolding assemblies of the implementation shown in FIG. 1.

FIG. 9 is an enlarged, fragmentary, side elevational view of thestroller frame of FIG. 2 in the fully unfolded state better illustratingone of the side folding assemblies.

FIG. 10 is a side elevational view of the stroller frame in the fullyunfolded state of FIG. 9 showing internal components of one of the sidefolding assemblies.

FIG. 11 is the side elevational view of the stroller frame in the fullyunfolded state of FIG. 9 with the internal components of the sidefolding assembly shown in broken line.

FIG. 12 is the side elevational view of the stroller frame of FIG. 11 inthe fully folded state with the internal components of the side foldingassembly shown in broken line.

DETAILED DESCRIPTION OF THE INVENTION

As shown in the drawings for purposes of illustration, the presentinvention is embodied in an all-terrain baby stroller 10, as shown inFIG. 1, having a foldable, tubular metal frame 12 and a transverselyextending rear axle assembly 14 with a transverse, non-rotating tubularrear axle 15. Left and right side rear wheels 16 are rotatably mountedto the ends of the rear axle assembly 14. The forward end of the flame12 has a single front wheel 15 rotatably mounted thereto.

The frame 12 has no base frame members extending rearwardly from thefront wheel 18 to the rear axle assembly 14 as do most conventionalall-terrain strollers. Instead, the frame 12 includes left and rightside, downwardly and forwardly sloping front wheels frame members orsupports 20, which each extend downward from a corresponding one of leftand right side folding assemblies 22 in a converging configuration tothe front wheel 18. A forward free-end 20 a of each of the left andright side front wheel supports 20 has a plastic front wheel connector(not shown) fixedly attached thereto and a corresponding one of the leftand right ends of an axle 18 a of the front wheel 18 removably attachedthereto to mount the front wheel to the stroller frame 12.

The front wheel supports 20 are interconnected by a foot rest 28 thatspans between they toward but rearward of their forward free-ends 20 aand that is fixedly attached to each at a position just above the frontwheel 18 and just rearward of the axle 18 a of the front wheel. As aresult of the interconnection provided by the foot rest 28, and also thefront wheel 18 when attached to the left and right side front wheelconnectors, the left and right side front wheel supports 20 form astationary unit with respect to the left and right side foldingassemblies 24 upon folding and unfolding of the stroller 10, will bedescribed in greater detail below.

The frame 12 also includes left and right side, upwardly and rearwardlysloping handle frame members or supports 24, which each extend upwardfrom the corresponding one of the left and right side folding assemblies22 in a generally parallel configuration to a handle 26 extendingbetween the left and right side handle supports. The handle 26 iscovered by a foam grip. The handle supports 24 are interconnected by thehandle 26 that spans between them at their rearwardmost and uppermostextension and that is fixedly attached to each.

As a result of the interconnection provided by the handle 26, the leftand right side handle supports 24 move as a unit with respect to theleft and right side folding assemblies 22 upon folding and unfolding ofthe stroller 10, as will be described in greater detail below. It isnoted that in lieu of the interconnecting handle 26, the handle supports24 may each be provided with a handle portion at the upper end thereofsuch as used with umbrella style strollers.

In the illustrated embodiment of the invention the left and right sidehandle supports 24 and the handle 26 are formed as an integral unit bybending a single length of aluminum tube. The left and right side handlesupports 24 are movable relative to the left and right side front wheelsupports 20 for folding of the stroller 10 and do not together form anintegrated rigid upper frame. The left and right side handle supports 24are also movable independent from movement of the left and right sidefront wheel supports 20.

The frame 12 also includes left and right side, downwardly andrearwardly sloping rear wheel frame members or supports 30, which eachextend downward from the corresponding one of the left and right sidefolding assemblies 22 in a generally parallel configuration to the maraxle assembly 14. A rearward free-end 30 a of each of the left and rightside mar wheel supports 30 is fixedly attached to a corresponding one ofthe left and right ends of the tubular rear axle 15. The rear wheelsupports 30 are interconnected by the rear axle assembly 14 that spansbetween them at the rearward free-ends 30 a thereof. As a result of theinterconnection provided by the rear axle assembly 14, the left andright side rear wheel supports 30 move as a unit with respect to theleft and right folding assemblies 22 for folding and unfolding of thestroller 10, as will be described in greater detail below. The left andright side rear wheel supports 30 are also movable relative to the leftand right side front wheel supports 20 and the left and right sidehandle supports 24 for folding of the stroller 10. Further, the left andright side rear wheel supports 30 and the rear axle assembly 14connected thereto do not form a part of a base frame extending betweenthe rear and front wheels 16 and 18. Much of the structural strength ofthe stroller 10 and the interconnection of the forward wheel supports20, the handle supports 2$, and the rearward wheel supports 30 areprovided by the centrally positioned left and right side foldingassemblies 22, and not by base frame.

In the illustrated embodiment of the stroller 10, the left and rightside front wheel supports 20, the left and right side handle supports24, and the left and right side rear wheel supports 30 are made fromaluminum tube. Suitable alternative materials may be used.

The left and right outward ends of the tubular rear axle 15 are open andinternally threaded to receive a threaded stub axle 32 forming a part ofthe corresponding one of the left and right rear wheels 16. A lock nut(not shown) when tightened against the face of the stub axle 32 locksthe stub axle against loosening during usage of the stroller 10.Alternative constructions may be used to fixedly or removably attach therear wheels 16 to the tubular rear axle 15, and any suitable alternativemanner of mounting the rear wheels 16 to the real wheel supports 30 maybe used with or without a park brake.

The frame 12 of the stroller 10 is shown in FIG. 1 in the fully unfoldedstate with a fabric seat 2, fabric leg support and guard 3. For purposesof illustration, the frame 12 is shown in FIG. 2 without the seat 2 andthe leg guard The seat 2 is suspended from the left and right sidehandle supports 24, and the leg guard 3 spans between and is supportedby the left and right side front wheel supports 20.

For the depicted implementation, user operation of the left and rightside folding assemblies 22 will now be described. The left and rightside folding assemblies 22 have the same construction, and thedescription below while in the singular is applicable to both. Each ofthe left and right rear wheel supports 30 supports an inwardly extendinglever 34, which has a predominantly vertical orientation, as shown inFIG. 3, when the frame 12 of the stroller 10 is locked in the fullyunfolded position. To begin the procedure to fold the frame 12, each ofthe levers 34 are pulled upward and inward as depicted by arrows R1 tothereby put the folding assemblies 22 in an unlocked state as furtherexplained below.

With each of the left and right folding assemblies 22 in an unlockedstate, the left and right handle supports 24, along with the handle 26,and the left and right forward wheel support 20, along with the forwardwheel 18, can be rotated about the left and right folding assemblies,respectively, toward the left and right rear wheel supports 30,respectively, as depicted by arrows R2 shown in FIG. 4. As stated, theforward wheel supports 20 can be moved independently from movement ofthe handle supports 24. In the process of folding the frame 12, if theforward wheel supports 20 were to be rotated about the foldingassemblies 22 before rotation of the handle supports 24 about thefolding assemblies, then the frame 12 would appear in a partially foldedstate as shown in the front elevational view of FIG. 5 and the sideelevational view of FIG. 6. In a fully folded state, both the forwardwheel supports 20 and the handle supports 24 have been rotated about thefolding assemblies 22 to be positioned in close proximity to the rearwheel supports 30 as shown in the side elevational view of FIG. 7.

As shown in FIG. 8, each of the folding assemblies 22 includes a forwardrotatable member 35′ having a disk 36′ with a notch 38′ and an arm 40′,and a rearward rotatable member 35″ having a disk 36″ with a notch 38″and an arm 40″. The disks 36′ and 36″ and the arms 40′ and 40″ aredepicted in FIG. 8 as being part of a single formed piece', however, inother implementations the disks and arms are individual pieces that arefixedly attached together. The rotatable members 35′ and 35″, along witha corresponding one of the rear wheel supports 30, are contained betweenleft and right slotted halves of a housing 42 that allow the arms 40′and 40″ to protrude outside of the housing. The inside wall of each halfof the housing 42 has recess 42 a sized and shaped such that when thetwo halves of the housing are positioned together, the recesses form acavity to securely receive the upper free-end portion of the rear wheelsupport 30 therein. The disks 36′ and 36″ each have a central aperture41′ and 41″, respectively, sized to receive a bushing 43 therethroughhaving a length longer than the cumulative thickness of the two disks.When the folding assembly 22 is assembled, the disks 36′ and 36″ arearranged facing each other with the bushing 43 extending through thealigned apertures 41′ and 41″ of the disks, and this subassembly ispositioned in a slot 30 b in the enlarged, upper free-end portion of thereal wheel support 30. The slot 30 b has a forward to rearwardorientation, A central aperture 43 a of the bushing 43 is aligned with apair of opposing inward and outward side apertures 30 c of the rearwheel support 30, transverse to the orientation of the slot 30 b, andthe left and right slotted halves of the housing 42 clamp around theslotted upper free-send portion of the rear wheel support 30. The leftand right slotted halves of the housing 42 have opposing apertures 42 b,which align with the central aperture 43 a of the bushing 43, such thata bolt 44 extends fully through the apertures 42 b of the halves of thehousing 42, through the aperture 30 c of the rear wheel support 30, andthrough the central aperture 43 a of the bushing 43. A nut 44 a isthreaded onto the threaded end of the bolt 44 to hold the assemblytogether with the disks 36′ and 36″ freely rotatable on the bushing 43.With this assembly, the bolt 44 and nut 44 a hold the left and rightslotted halves of the housing 42 securely clamped together with theslots of the housing having the arms 40′ and 40″ extending therethrough.The arm 40′ extends forwardly through the forward opening of the slot 30b and the other arm 40″ extends rearwardly through the rearward openingof the slot 30 b in the rear wheel support 30.

When the folding assemblies 22 are in a fully unfolded state, as shownin FIG. 9, the disks 36′ and 36″ of the folding assembly are locked inplace by components positioned internal to the rear wheel supports 30including a slidably mounted head 50 with a tip 52 inserted into thenotches 38′ and 38″ as shown in FIG. 10. In FIG. 10, a cover portion 30d of the upper free-end portion of the rear wheel support 30 is shownremoved in order to better illustrate the components of the foldingassembly 22 contained therein. The cover portion 30 d is attached to theother portion of the free-end portion of the rear wheel support 30 by abolt 30 e, as seen in FIG. 9. The lever 34 is pivotally mounted to therear wheel support 30 and the head 50 is mechanically linked to thelever 34 so that when the lever 34 is pulled upward and inward asdepicted by the arrows R1 in FIG. 5, the head 50 is moved away from thedisks 36′ and 36″, thereby causing the tip 52 to be retracted anddisengaged from the notches 38′ and 38″. The disks 36′ and 36″ are thenfree to rotate on the bolt 44 and hence allow folding of the front wheelsupport 20 and the handle support 24 about the rear wheel support 30 ina clam shell movement, as will be explained in greater detail below.

The head 50 further includes a base 54, which rests against one end of aspring 56. The other end of the spring 56 rests against an internalsupport 58 inside the rear wheel support 30 such that the springprovides a force adequate to bias the tip 52 into an engaged statewithin the notches 38′ and 38″ of the disks 36′ and 36″ when the foldingassembly 22 is in the fully unfolded state. While supplying a force tothe head 50 to keep the tip 52 in the notches 38′ and 38″, the force isnot so great as to require undue force to be applied to the lever 34 bythe user to retract and disengage the tip from the notches when thefolding assembly is to be folded.

The internal support 58 is coupled to or may be an integral part of therearward free-end 30 a of the rear wheel support 30 to couple thefolding assembly 22 to the rear axle assembly 14. As shown in FIGS. 11and 12, for each of the folding assemblies 22 on the left and rightsides of the stroller 12, the front wheel support 20 is bolted onto thearm 40′ of the forward rotatable member 35′ using a pair of bolts 60,and the handle support 24 is bolted onto the arm 40″ of the rearwardrotatable member 35″ using a pair of bolts 62.

In the fully folded state of the stroller 12, both the front wheelsupport 20 and the handle support 24 are moved into aloe proximity tothe rear wheel support 30. As shown in FIG. 12, in the fully foldedstate, the tip 52 of the head 50 is retracted and disengaged from thenotch 38′ of the forward rotatable member 35′ and the notch 38″ of therearward rotatable member 35″. In the fully folded state, both the frontwheel support 20 and the handle support 24 are free to rotateindependently of the other about the bolt 44 of the folding assembly 22so that the notches 38′and 38″ can be brought back into alignment withthe tip 52 of the head 60 to consequently secure the stroller 12 intothe fully folded state.

From the foregoing it will be appreciated that, although specificembodiments of the invention have been described herein for purposes ofillustration, various modifications may be made without deviating fromthe spirit and scope of the invention. For instance, the depictedimplementation used the bolt 44 and nut 44 a assembly to rotatablycouple the forward rotatable member 35′ and the rearward rotatablemember 35″ together with a corresponding one of the rear wheel supports30. In other implementations, pivot members other than the bolt-nutassembly may be used, including pin assemblies. As another example, inthe depicted implementation, the rear wheel supports 30 supported hebolt 44 on which the rotatable members 35′ and 35″ where rotatablymounted. In other implementations, either the front wheel support 20 cansupport the bolt 44 and have the rotatable members 35′ and 35″ rotatablymounted thereon with the arms 40′ and 40″ each fixedly attached to oneof the handle support 24 and the rear wheel support 30 such that thehandle support and the rear wheel support fold about the front wheelsupport, or the handle support 24 can support the bolt 44 and have therotatable members 35′ and 35″ rotatably mounted thereon with the arms40′ and 40″ each fixedly attached to one of the front wheel supports 20and the rear wheel support 30 such that the front wheel support and thereal wheel support fold about the handle support. As a further example,the rotatable members 35′ and 35″ were depicted as including the disks36′ and 36″, however, in other implementations the rotatable members 35′and 35″ may have other shapes. As an additional example, the depictedimplementation aligned the tip 52 of the spring loaded head 50 of eachfolding assembly 22 with the notches 38′ and 38″ of the disks 36′ and36″ to secure the stroller 12 into the fully folded state. In otherimplementations, each folding assemblies 22 can use a pin or othermember that is inserted into holes in each of the disks 36′ and 36″ tohold the front wheel supports 20, the handle supports 24, and the rearwheel supports 30 in the unfolded state. Accordingly, the invention isnot limited except as by the appended claims.

1-11. (canceled)
 12. A folding assembly for a foldable stroller having afront wheel support, a handle member and a rear wheel support movableinto an unfolded state, the folding assembly, comprises: a firstrotatable member rotatably mounted on a pivot member; and a secondrotatable member rotatably mounted on the pivot member to rotaterelative to the first rotatable member about the pivot member as acommon axis, the first rotatable member being configured for attachmentto the front wheel support for movement therewith, and the secondrotatable member being configured for attachment to the handle memberfor movement therewith; the folding assembly further comprising alocking member slidably mounted to the rear wheel support, and the firstand second rotatable members each further comprising a hole to receivethe locking member therein when the first and second rotatable membersare rotated about the pivot member to position the foldable strollerinto an unfolded state, thereby supporting and locking the foldingassembly in the unfolded state.
 13. The folding assembly of claim 12,wherein the front wheel support and the handle portion move towards andapproach opposite sides of the rear wheel support when the foldingassembly is moved from an unfolded state to a folded state.
 14. Thefolding assembly of claim 13, wherein the first and second rotatablemembers each have a planar arm projecting therefrom and in coplanarrelation therewith, the front wheel support being fixedly attached tothe planar arm of the first rotatable member and the handle member beingfixedly attached to the planar arm of the second rotatable member. 15.The folding assembly of claim 14, further comprising an enclosure withinwhich the first and second rotatable members and the rear wheel supportare retained.
 16. The folding assembly of claim 15, wherein the lockingmember rests against a spring such that the spring provides a forceadequate to bias the locking member into an engaged state within theholes of the first and second rotatable members.
 17. The foldingassembly of claim 16, wherein the holes of the first rotatable memberand the second rotatable member are in alignment when the foldingassembly is in an unfolded state.
 18. The folding assembly of claim 14,wherein the front wheel support is bolted onto the planar arm of thefirst rotatable member and the handle member is bolted onto the planararm of the second rotatable member.
 19. A foldable baby stroller framefor use with at least one front wheel and at least one rear wheel,comprising: left and right side laterally spaced-apart first members,each of the first members having a first end portion and a second endportion; left and right side laterally spaced-apart second members, eachof the second members having a first end portion and a second endportion; left and right side laterally spaced-apart third members, eachof the third members having a first end portion and a second endportion, at least one of the first end portions of the first membershaving a mounting portion configured for mounting of the at least onefront wheel thereto, at least one of the first end portions of thesecond members having a mounting portion configured for mounting of theat least one rear wheel thereto, and at least one of the first endportions of the third members having a handle portion; and left andright side laterally spaced-apart folding assemblies, each of the leftand right side folding assemblies having a first rotatable member and asecond rotatable member rotatably mounted on a pivot member to pivotabout the pivot member as a common axis, one of the second end portionsof a first one of the first, second, and third members being fixedlyattached to the first rotatable member, one of the second end portionsof a different second one of the first, second, and third members beingfixedly attached to the second rotatable member, and one of the secondend portions of another different third one of the first, second, andthird members supporting the pivot member, wherein the left and rightfolding assemblies each further include a locking member mounted to thecorresponding one of the left and right side another different third oneof the first, second, and third members supporting the pivot member, andthe first and second rotatable members of each folding assembly furtherinclude a hole to receive the locking member therein when the first andsecond rotatable members are rotated about the pivot member to positionthe handle member, the front wheel support and the rear wheel support inan unfolded state.
 20. The foldable baby stroller frame of claim 19,wherein the first and second rotatable members are first and secondplates, respectively, arranged in juxtaposition.
 21. The foldable babystroller frame of claim 20, wherein the first and second plates eachhave a planar arm projecting therefrom and in coplanar relationtherewith, the one of the second end portions attached to the firstrotatable member being fixedly attached to the arm of the first plateand the one of the second end portions attached to the second rotatablemember being fixedly attached to the arm of the second plate.
 22. Thefoldable baby stroller frame of claim 21, wherein the first and secondplates each have a central aperture and wherein the pivot memberincludes a bushing passing through the central apertures of the firstand second plates for rotation thereabout.
 23. The foldable babystroller frame of claim 20, wherein the one of the second end portionssupporting the pivot member includes a chamber within which the firstand second plates are rotatably positioned.
 24. The foldable babystroller frame of claim 23, wherein the one of the second end portionssupporting the pivot member includes laterally inward and outward wallportions defining the chamber therebetween.
 25. The foldable babystroller frame of claim 19, wherein the one of the second end portionssupporting the pivot member includes laterally inward and outward wallportions defining a chamber therebetween, the first and second rotatablemembers being rotatably positioned within the chamber.
 26. The foldablebaby stroller frame of claim 25, wherein the chamber has a forwardopening and a rearward opening, and wherein each of the first and secondrotatable members includes an attachment portion for attachment to thesecond end portions of the first and different second ones of the first,second, and third members fixedly attached to the first and secondrotatable members, the attachment portion of one of the first and secondrotatable members extending forward through the forward opening and theattachment portion of the other of the first and second rotatablemembers extending rearward through the rearward opening.
 27. A foldingassembly usable with a foldable device having first, second and thirdframe members movable into an unfolded state, comprising: a firstrotatable member rotatably mounted on a pivot member; and a secondrotatable member rotatably mounted on the pivot member to rotaterelative to the first rotatable member about the pivot member as acommon axis in first and second spaced apart rotational planes,respectively, the first rotatable member being configured for attachmentto a first one of the first, second and third frame members for movementtherewith, the second rotatable member being configured for attachmentto a different second one of the first, second and third frame membersfor movement therewith, and the pivot member being configured forsupport by a different third one of the first, second and third framemembers, a locking member, and the first and second rotatable memberseach further include a hole to receive the movable member therein whenthe first and second rotatable members are rotated about the pivotmember to position the first, second and third frame members in theunfolded state.
 28. The folding assembly of claim 27, wherein thelocking member is configured for support by the different third one ofthe first, second and third frame members.
 29. The folding assembly ofclaim 27, wherein the locking member is a pin.
 30. The folding assemblyof claim 27, wherein the locking member rests against a spring such thatthe spring provides a force adequate to bias the locking member into anengaged state within the holes of the first and second rotatablemembers.
 31. The folding assembly of claim 27, wherein the holes of thefirst rotatable member and the second rotatable member are in alignmentwhen the folding assembly is in an unfolded state.